Recent intense beam experiments in microwave radiation are considered within the context of strong turbulence theory of the beam‐plasma instability. A weak turbulence model for radiation at the plasma fundamental gives qualitatively correct power levels and suggests that the radiation itself is an important dynamical entity in the beam‐plasma instability. Radiation in the region &ohgr;∼2&ohgr;pis weak, in agreement with experiment. Plasma inhomogeneities in the experiment of size approximately 0.3 cm can explain the low‐frequency emission power level, and its dependence on the plasma density and external magnetic field. Understanding these processes may lead to use of radiation as a versatile diagnostic measurement of beam‐plasma systems.